The quest for a high power, electrically driven laser with excellent thermal management, lightweight packaging, and high brightness for tactical military applications may be realized with the advent of the Diode Pumped Alkali Laser (DPAL). The concept of using a gas phase medium for the phasing of large diode arrays via a highly efficient, cyclical photon engine combines the best features of electrically driven lasers with the inherent thermal management advantages of a gas lasers. Indeed, the DPAL concept has sparked great interest within the Directed Energy community resulting in a number of recent low power, highly efficient laser demonstrations. A modest national effort is underway to exploit this technology for military applications. Early laser demonstrations of the Diode Pumped Alkali Laser achieved output powers of 1-3 W in both rubidium and cesium with slope efficiencies as high as 82%. More recently, cw output powers as high as 145 W with in-band slope efficiencies of 28% have been reported. The system is a three level laser pumped by diode bars on the D2 transition, exciting the first 2P3/2 state of the alkali atom. Collisional relaxation to the 2P1/2 state is accomplished with a spin orbit relaxing gas such as ethane or methane, while pressure broadening of the absorption line has routinely been accomplished with He. The excited alkali atom then lases on the D1 line back to the ground state. Terminating the laser level at the ground state requires the gain volume to be fully bleached before achieving an inversion between the 2P1/2 and 2S1/2 states, resulting in pump threshold values of ~1 kW/cm2. This course will develop the background spectroscopy and kinetics of the DPAL system, summarize recent laser demonstrations, discuss narrow banding of diode pump sources, develop the key performance and scaling equations, and outline several issues in the development of these devices.